Light emitting device having a reflective member

ABSTRACT

The present disclosure relates to a light-emitting device. The light-emitting device includes a substrate, a first light-emitting chip, a first wavelength conversion member, and a barrier member. The first light-emitting chip is mounted on the substrate. The first wavelength conversion member covers the upper surface of the first light-emitting chip. A first reflective member covers the side surface of the first wavelength conversion member. Further, the barrier member includes an outer wall surrounding the side surfaces of the first light-emitting chip and the first reflective member.

CROSS-REFERENCE OF RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/819,687, filed on Mar. 16, 2020, which is a continuation of PCTApplication No. PCT/KR2019/000360, filed on Jan. 9, 2019, which claimspriority under 35 U.S.C. § 119 of Korean Patent Application No.1020180003312, filed on Jan. 10, 2018 and Korean Patent Application No.1020190000235, filed on Jan. 2, 2019. The disclosures of theaforementioned applications are hereby incorporated by reference intheir entireties.

TECHNICAL FIELD

Embodiments of the present disclosure relate to a light emitting device.

BACKGROUND

A light emitting chip refers to a semiconductor device that emits lightthrough recombination of electrons and holes. The light emitting chip isused in various fields, such as displays, vehicle lamps, generallighting, and the like. Since the light emitting chip has long lifespan,low power consumption, and rapid response rate, the light emitting chipis applied to various fields including vehicle lamps and displays.

FIG. 1 is a cross-sectional view of a conventional light emitting device10. Referring to FIG. 1, the light emitting device 10 includes lightemitting chips 11, wavelength conversion members 12, a barrier member14, and a circuit board 15. The barrier member 14 is formed of a resincontaining a reflective material. Thus, the barrier member 14 serves toreflect light emitted from the light emitting chips 11. However, in theconventional light emitting device 10, some fraction of light emittedfrom the light emitting chips 11, or having passed through a sidesurface of the wavelength conversion members 12 passes through thebarrier member 14, instead of being reflected by the reflectivematerial. In particular, the light emitting device 10 has a shortdistance between a side surface and an upper surface at a corner portionof the barrier member 14 adjacent to the wavelength conversion member12. That is, a smaller amount of the reflective material is distributedat the corner portion of the barrier member 14 than other portionsthereof, thereby allowing some fraction of light to pass through thecorner portion of the barrier member 14. As a result, the light emittingdevice 10 suffers from light blurring caused by light leakage to a sidesurface thereof in addition to a front region thereof to be irradiatedwith light.

FIG. 2 is a graph depicting brightness of the conventional lightemitting device. Referring to FIG. 2, Portion A1 shows that light istenuously emitted from a portion of the barrier member 14 adjoining afirst wavelength conversion member 12, instead of being completelyblocked thereby. In addition, Portion B1 shows that light is alsoemitted from a portion of the barrier member 14 between the firstwavelength conversion member 12 and a second wavelength conversionmember 12. Further, Portion C1 shows that light is emitted from aportion of the barrier member 14 adjoining the second wavelengthconversion member 12.

When light blurring occurs on a side surface of a light emitting deviceapplied to a vehicle lamp, a cutoff line is not clearly formed at theborder between a dark portion and a bright portion upon irradiation withlight emitted in front of the vehicle lamp. As a result, an unnecessaryregion can be irradiated with light by a driver, thereby interferingwith other driver's visual fields, and light can be emitted to a side ofthe light emitting device, thereby causing a problem of light loss.

SUMMARY

Embodiments of the present disclosure provide a light emitting devicecapable of preventing light blurring. Embodiments of the presentdisclosure provide a light emitting device capable of preventing lightloss. Embodiments of the present disclosure provide a light emittingdevice capable of simultaneously preventing reduction in luminous areaand light blurring.

In accordance with one embodiment of the present disclosure, a lightemitting device includes a substrate, a first light emitting chip, afirst wavelength conversion member, and a barrier member. The firstlight emitting chip is mounted on the substrate. The first wavelengthconversion member covers an upper surface of the first light emittingchip. A first reflective member covers a side surface of the firstwavelength conversion member. In addition, the barrier member includesan outer wall covering side surfaces of the first light emitting chipand the first reflective member.

The light emitting device according to embodiments of the presentdisclosure employs a reflective member to prevent light from passingthrough a barrier member, thereby preventing light blurring.

In addition, the light emitting device according to embodiments of thepresent disclosure can prevent light blurring, thereby preventing lightloss.

Further, the light emitting device according to embodiments of thepresent disclosure can prevent light blurring, thereby securing otherdriver's long visual fields including vehicles at an opposite side whenapplied to a vehicle lamp.

Further, the light emitting device according to embodiments of thepresent disclosure can simultaneously prevent reduction in luminous areaand light blurring using a reflective member.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of a conventional light emittingdevice.

FIG. 2 is a graph depicting brightness of the conventional lightemitting device.

FIG. 3 and FIG. 4 are views of a light emitting device according to afirst embodiment of the present disclosure.

FIG. 5 and FIG. 6 are views of a light emitting device according to asecond embodiment of the present disclosure.

FIG. 7 and FIG. 8 are views of a light emitting device according to athird embodiment of the present disclosure.

FIG. 9 is a graph depicting brightness of the light emitting deviceaccording to the third embodiment of the present disclosure.

FIG. 10 and FIG. 11 are views of a light emitting device according to afourth embodiment of the present disclosure.

FIG. 12 and FIG. 13 are views of a light emitting device according to afifth embodiment of the present disclosure.

FIG. 14 is a view of a light emitting device according to a sixthembodiment of the present disclosure.

FIG. 15 is a view of a light emitting device according to a seventhembodiment of the present disclosure.

FIG. 16 and FIG. 17 are views of a light emitting device according to aneighth embodiment of the present disclosure.

FIG. 18 is a view of a light emitting device according to a ninthembodiment of the present disclosure.

FIG. 19 to FIG. 21 are views of light emitting devices according totenth and eleventh embodiments of the present disclosure.

FIG. 22 to FIG. 25 are views of light emitting devices according totwelfth to fifteenth embodiments of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be described indetail with reference to the accompanying drawings. The followingembodiments are provided by way of example so as to fully convey thespirit of the present disclosure to those skilled in the art to whichthe present disclosure pertains. Accordingly, the present disclosure isnot limited to the embodiments disclosed herein and can also beimplemented in different forms. In the drawings, widths, lengths,thicknesses, and the like of elements can be exaggerated for clarity anddescriptive purposes. Throughout the specification, like referencenumerals denote like elements having the same or similar functions.

In accordance with one embodiment of the present disclosure, a lightemitting device includes a substrate, a first light emitting chip, afirst wavelength conversion member, and a barrier member. The firstlight emitting chip is mounted on the substrate. The first wavelengthconversion member covers an upper surface of the first light emittingchip. The first reflective member covers a side surface of the firstwavelength conversion member. In addition, the barrier member includesan outer wall covering side surfaces of the first light emitting chipand the first reflective member.

An upper portion of the outer wall of the barrier member may have athickness gradually increasing from an upper surface thereof in adownward direction thereof. Alternatively, the barrier member may have aflat upper surface.

For example, the first light emitting chips may be mounted in plural onthe substrate.

An upper portion of the outer wall of the barrier member disposedbetween the first light emitting chip and a side surface of thesubstrate may have a thickness gradually increasing from an uppersurface thereof in a downward direction thereof. In addition, an innerwall of the barrier member disposed between the first light emittingchips may have a convex upper portion.

Further, the outer wall of the barrier member may contain a largeramount of fillers than the inner wall thereof.

The light emitting device may include the first wavelength conversionmember and the first reflective member on each of the first lightemitting chips.

Here, each of the first reflective members may be spaced apart fromanother first reflective member adjacent thereto.

For example, the first reflective member may cover a side surface of thewavelength conversion member and a side surface of the first lightemitting chip.

The first reflective member may include at least one selected fromsilver (Ag) and aluminum (Al).

The first wavelength conversion member may have a greater width than orthe same width as the first light emitting chip.

The first wavelength conversion member may include a mixture of awavelength conversion material and one of an epoxy resin, a siliconeresin, glass and a ceramic material. The first wavelength conversionmember may further include a reflective material.

For example, the light emitting device may further include a secondreflective member covering an upper surface of the barrier member.

The second reflective member may be disposed to contact an upper surfaceof the first reflective member.

The second reflective member may cover the upper surface of the firstreflective member or may be formed along a periphery of the uppersurface of the first reflective member, and may cover a portion of theupper surface of the barrier member. Alternatively, the secondreflective member may cover the entirety of the upper surface of thebarrier member or may cover the entirety of the upper surface of thebarrier member and the upper surface of the first reflective member.

The second reflective member may include at least one selected fromsilver (Ag) and aluminum (Al).

The substrate may be a circuit board including an insulation layer and acircuit pattern.

The circuit pattern may include a first circuit pattern, a secondcircuit pattern, and a via. The first circuit pattern may be formed onan upper surface of the insulation layer and may be electricallyconnected to the first light emitting chip. The second circuit patternmay be formed on a lower surface of the insulation layer. In addition,the via may electrically connect the first insulation pattern to thesecond insulation pattern through the insulation layer.

One end of the first circuit pattern may be disposed in the middlebetween one side surface of the first light emitting chip and the outerwall of the barrier member. Alternatively, one end of the first circuitpattern may be disposed between the outer wall of the barrier member andthe middle between one side surface of the first light emitting chip andthe outer wall of the barrier member.

The via may have a width gradually decreasing from upper and lowersurfaces of the insulation layer to an interior thereof.

The plurality of first light emitting chips may be arranged parallel toeach other from one side of the substrate to the other side thereof.Here, the first wavelength conversion member may have a width equal to awidth from one side surface of the first light emitting chip disposed atthe one side to one side surface of the first light emitting chipdisposed at the other side. Here, the one side surface of the firstlight emitting chip may face an inner wall of the barrier member.

For example, the light emitting device may further include a secondlight emitting chip spaced apart from the first light emitting chip in alateral direction. The second light emitting chip may be disposed suchthat one side surface of the second light emitting chip faces one sidesurface of the first light emitting chip.

The light emitting device may further include a second wavelengthconversion member covering an upper surface of the second light emittingchip.

The second wavelength conversion member may include a mixture of awavelength conversion material and one of an epoxy resin, a siliconeresin, glass and a ceramic material.

The first wavelength conversion member and the second wavelengthconversion member may include different wavelength conversion materialsto convert light into different wavelengths.

The barrier member may further include an inner wall disposed betweenthe first light emitting chip and the second light emitting chip. Here,the inner wall of the barrier member may have a convex upper surface.

The outer wall of the barrier member may contain a larger amount offillers than the inner wall thereof.

The light emitting device may further include a protective memberdisposed between the first reflective member and the barrier member toprotect the first reflective member.

The protective member may include at least one layer selected from asilicon nitride (SiNx) layer, a silicon oxide (SiO₂) layer and a gold(Au) layer.

The second wavelength conversion member may further include a reflectivematerial.

Hereinafter, various embodiments of the present disclosure will bedescribed with reference to the accompanying drawings.

FIG. 3 and FIG. 4 are views of a light emitting device according to afirst embodiment of the present disclosure. FIG. 3 is a top view of thelight emitting device 100 according to the first embodiment. FIG. 4 is across-sectional view of the light emitting device 100 according to thefirst embodiment.

Referring to FIG. 3 and FIG. 4, the light emitting device 100 includes alight emitting chip 110, a wavelength conversion member 120, areflective member 130, a barrier member 140, and a circuit board 150.

The light emitting chip 110 may be a light emitting diode chip thatemits light. The light emitting chip 110 is disposed on the circuitboard 150 to be electrically connected to the circuit board 150. Forexample, the light emitting chip 110 may be formed at a lower sidethereof with electrode pads (not shown). Here, the electrode pads of thelight emitting chip 110 may be electrically connected to a first circuitpattern 151 formed on an upper surface of the circuit board 150 via anelectrically conductive bonding material.

The wavelength conversion member 120 is disposed on the light emittingchip 110. The wavelength conversion member 120 may be formed to cover anupper surface of the light emitting chip 110. The wavelength conversionmember 120 may have the same width as the light emitting chip 110. Thatis, side surfaces of the wavelength conversion member 120 may bedisposed collinearly with side surfaces of the light emitting chip. Thewavelength conversion member 120 serves to convert light emitted fromthe light emitting chip 110 so as to emit white light or a particularcolor.

The wavelength conversion member 120 may be formed of a mixture of atransparent resin, such as a silicone resin or an epoxy resin, glass ora ceramic material and a wavelength conversion material that convertswavelengths of light. For example, the transparent resin may be atransparent silicone resin. The wavelength conversion material may bephosphors. The phosphors may include yellow phosphors, red phosphors,green phosphors, and the like.

Examples of the yellow phosphors may include YAG:Ce (T₃Al₅O₁₂:Ce)-basedphosphors, which are cerium (Ce)-doped yttrium (Y)-aluminum (Al)garnets, and silicate-based phosphors, which have a main wavelength of530 nm to 570 nm.

Examples of the red (R) phosphors may include YOX (Y₂O₃:EU))-basedphosphors composed of a compound of yttrium oxide (Y₂O₃) and europium(Eu), and nitride phosphors, which have a main wavelength of 611 nm.

Examples of the green (G) phosphors may include LAP (LaPO4:Ce,Tb)-basedphosphors having a main wavelength of 544 nm and composed of a compoundof phosphate (PO₄), lanthanum (La) and terbium (Tb).

Examples of the blue (B) phosphors may include BAM(BaMgAl₁₀O₁₇:EU)-based phosphors having a main wavelength of 450 nm andcomposed of a compound of a barium (Ba), magnesium (Mg), aluminum oxidematerial and europium (Eu).

The phosphors may include fluoride compound KSF phosphors (K₂SiF₆),which are Mn⁴⁺ active phosphors advantageous for high colorreproduction.

For example, the wavelength conversion member 120 may be formed ofphosphor-in-glass (PIG) which is a mixture of glass and phosphors. Thewavelength conversion member 120 formed of PIG can efficiently preventintrusion of foreign matter, such as moisture, dust and the like, intothe light emitting device 100.

The wavelength conversion member 120 may further contain a reflectivematerial. The reflective material may have a melting point so as not tobe melted upon sintering of the wavelength conversion member 120. Forexample, the wavelength conversion member 120 formed of PIG may furthercontain silicon dioxide (SiO₂) as the reflective material.

The reflective member 130 is formed to surround side surfaces of thewavelength conversion member 120, as shown in FIGS. 3 and 4. Thereflective member 130 prevents light emitted from the light emittingchip 110 from passing through the barrier member 140. That is, thereflective member 130 reflects light. Alternatively, the reflectivemember 130 may be formed of a material capable of reflecting light, orabsorbing light without allowing the light to pass therethrough. Forexample, the reflective member 130 may be formed of at least oneselected from silver (Ag) and aluminum (Al). The reflective member 130formed of silver has high reflectivity with respect to light. Thereflective member 130 formed of aluminum exhibits high adhesion to thewavelength conversion member 120 or the barrier member 140. In this way,the reflective member 130 may have a single layer structure composed ofsilver or aluminum with reference to reflectivity or adhesion.Alternatively, the reflective member 130 may have a multilayer structureof aluminum-silver-aluminum to enhance both adhesion and reflectivity.Although not shown in the drawings, at least one layer composed ofnickel (Ni) and titanium (Ti) may be further disposed on the reflectivemember 130. It should be noted that the material for the reflectivemember 130 is not limited to aluminum and silver and may include anymaterial capable of reflecting light emitted from the light emittingchip 110.

The barrier member 140 is formed to surround the side surfaces of thereflective member 130 and the light emitting chip 110. For example, thebarrier member 140 may be formed of a silicone resin. Alternatively, thebarrier member 140 may be formed of a silicone resin containing areflective material.

Conventionally, in order to secure alignment of the light emitting chipand the wavelength conversion member while preventing light blurring,the wavelength conversion member has a lower surface having a smallerarea than the upper surface of the light emitting chip. However, whenthe lower surface of the wavelength conversion member has a smaller areathan the upper surface of the light emitting chip, the overall intensityof light emitted from the light emitting device may be reduced.

In this embodiment, in order to increase the intensity of light emittedfrom the light emitting device, the lower surface of the wavelengthconversion member 120 is formed to have a larger area than the uppersurface of the light emitting chip 110. Here, in the light emittingdevice 100 according to this embodiment, since the area of thewavelength conversion member 120 is increased, the thickness of the sidesurface of the barrier member 140 is relatively reduced. However, sincelight emitted from the light emitting chip 110 is reflected by thereflective member 130, the light emitting device 100 can prevent lightblurring due to transmission of the light through the barrier member140.

More preferably, in consideration of the overall luminous intensity andbrightness, the light emitting device 100 is formed such that the uppersurface of the light emitting chip 110 has the same area as the lowersurface of the wavelength conversion member 120, as shown in FIG. 4.Here, the reflective member 130 prevents light emitted from the lightemitting chip 110 from passing through the barrier member 140, therebypreventing light blurring.

With the structure wherein not only the reflective member 130 but alsothe wavelength conversion member 120 further contains the reflectivematerial, the light emitting device 100 can achieve further improvementin the effect of reflecting light so as not to prevent the light frompassing through the barrier member 140.

According to this embodiment, the side surface of the reflective member130 is formed to protrude relative to the light emitting chip 110, asshown in FIG. 4. Accordingly, the light emitting device has a largerbonding area of the barrier member 140 to components inside the barriermember 140 than a structure where the reflective member 130 is notpresent. As a result, coupling strength between the barrier member 140,the reflective member 130 and the light emitting chip 110 increases.

According to this embodiment, in order to prevent the barrier member 140from covering an upper surface of the wavelength conversion member 120,a material for the barrier member 140 is deposited to a smaller heightthan the wavelength conversion member 120. Here, the barrier member 140has a structure wherein an upper surface of the barrier member 140 has aheight gradually decreasing from an inner wall to an outer wall, asshown in FIG. 4. That is, an upper portion of the barrier member 140 hasa gradually increasing thickness in a downward direction thereof.Referring to FIG. 4, the thickness of the barrier member 140 graduallyincreases in the sequence of portion t1 of the barrier member 140 formedat one side of an upper portion of the reflective member 130, portion t2of the barrier member 140 formed at one side between the upper portionof the reflective member 130 and a lower portion thereof, and portion t3of the barrier member 140 formed at one side of the lower portion of thereflective member 130.

According to this embodiment, the reflective member 130 is disposedbetween the wavelength conversion member 120 and the barrier member 140.Accordingly, light emitted from the light emitting chip and travelingtowards the wavelength conversion member 120 is reflected by thereflective member 130, thereby preventing transmission of light throughthe barrier member 140. As a result, the light emitting device canprevent light blurring around the periphery of the wavelength conversionmember 120. In addition, even with the structure wherein the barriermember 140 is formed to a smaller height than the wavelength conversionmember 120 such that the upper portion of the barrier member 140 has agradually decreasing thickness, the light emitting device can preventlight blurring using the reflective member 130. Further, the lightemitting device 100 according to this embodiment can prevent unnecessarylight leakage using the reflective member 130, thereby preventing lightloss.

Further, the light emitting device includes the reflective member 130that reflects light, whereby the barrier member 140 can be formed to asmall thickness, thereby enabling reduction in width or size of thelight emitting device.

The circuit board 150 includes an insulation layer 153, a first circuitpattern 151, a second circuit pattern 152, and a via hole 154. Theinsulation layer 153 may be formed of a typical insulation material suchas an epoxy resin or prepreg, generally used for a printed circuitboard.

The first circuit pattern 151 is formed on an upper surface of theinsulation layer 153. The first circuit pattern 151 is electricallyconnected to the electrode pad of the light emitting chip 110. Anelectrically conductive bonding material 160 may be formed for bondingbetween the light emitting chip 110 and the first circuit pattern 151.For example, the bonding material 160 may include one of a solder pasteincluding Sn and at least one selected from Pb, Cu, Ag, Au, Zn, Al, Bi,and In, a silver (Ag) paste, and a silicon (Si) paste. It should beunderstood that the bonding material 160 is not limited to these pastesand may include any electrically conductive material capable of bondingthe circuit board 150 to the light emitting chip 110.

The second circuit pattern 152 is formed on a lower surface of theinsulation layer 153. Although not shown in the drawings, the secondcircuit pattern 152 is electrically connected to an external component.

The via hole 154 is formed to pass through the insulation layer 153. Thevia hole 154 may be formed by forming a through-hole in the insulationlayer 153, followed by filling the through-hole with an electricallyconductive material.

The first circuit pattern 151, the second circuit pattern 152 and thevia hole 154 are formed of a typical electrically conductive materialwell-known in the field of circuit boards. For example, the firstcircuit pattern 151, the second circuit pattern 152 and the via hole 154may be formed of copper (Cu).

The first circuit pattern 151 may have one end disposed at least betweenone side surface of the light emitting chip 110 and the outer wall ofthe barrier member 140. That is, the first circuit pattern 151 may beformed to have a length that allows the one end of the first circuitpattern to be placed in the middle between one side surface of the lightemitting chip 110 and the outer wall of the barrier member 140 orbetween the middle and the outer wall of the barrier member 140. Thefirst circuit pattern 151 is not exposed from the barrier member 140 andis formed over an area as large as possible, thereby improving heatdissipation of the light emitting device 100. The second circuit pattern152 may also be formed to have a long length like the first circuitpattern 151. Thus, the second circuit pattern has a large area, therebyimproving heat dissipation of the light emitting device 100. Further,the structure of the second circuit pattern 152 having a long lengthincreases the length of a moisture penetration path between theinsulation layer 153 and the second circuit pattern 152, therebypreventing moisture from affecting the light emitting chip 110.Furthermore, the bonding strength of the first circuit pattern 151 andthe second circuit pattern 152 to the insulation layer 153 alsoincreases.

The via hole 154 has a gradually decreasing width from the upper surfaceof the insulation layer 153 to the lower surface thereof. With thisstructure, the via hole 154 increases the length of the moisturepenetration path, thereby preventing moisture from affecting the lightemitting chip 110. In addition, a bonding area between the via hole 154and the insulation layer 153 increases, thereby increasing couplingstrength between the via hole 154 and the insulation layer 153.

In a conventional light emitting device which does not include thereflective member 130 as described according to this embodiment, thebarrier member contains a reflective material. However, the barriermember containing the reflective material allows some fraction of lightto pass through an upper portion of the barrier member. This is causedby a low density of the reflective material due to a small thickness ofthe upper portion of the barrier member or a corner portion thereof evenwith the structure where the upper portion of the barrier member is notthin. As a result, the conventional light emitting device may show lightblurring along the periphery of the wavelength conversion member 120. Ifthe conventional light emitting device applied to a vehicle lamp suffersfrom severe light blurring, it is necessary to adjust lamp lighting toface downwards so as not to interfere with other drivers' visual fields.As such, a vehicle lamp including the conventional light emitting devicehas a restricted lighting distance.

As in the embodiment of the present disclosure, if the problem of lightblurring can be solved using the reflective member 130, it is possibleto secure a longer visual field of a vehicle driver without interferingwith visual fields of other vehicle drivers including drivers ofvehicles in an opposite direction.

The following description will be given as to other embodiments of thepresent disclosure. Here, detailed description of the same components asthose of the first embodiment will be omitted. For the omitteddescription, refer to the description of the light emitting device 100according to the above embodiment shown in FIG. 3 and FIG. 4.

FIG. 5 and FIG. 6 are views of a light emitting device according to asecond embodiment of the present disclosure. FIG. 5 is a top view of thelight emitting device 200 according to the second embodiment. FIG. 6 isa cross-sectional view of the light emitting device 200 according to thesecond embodiment.

The light emitting device 200 according to the second embodimentincludes a plurality of light emitting chips, a wavelength conversionmember 120, a reflective member 130, a barrier member 140, and a circuitboard 150. Referring to FIG. 5 and FIG. 6, the plurality of lightemitting chips may include first to fourth light emitting chips 211 to214. Although four light emitting chips are illustrated in thisembodiment, the number of light emitting chips may be changed.

The first to fourth light emitting chips 211 to 214 may emit the samecolor, or at least one of the first to fourth light emitting chips 211to 214 may emit light of a different color. According to thisembodiment, the first to fourth light emitting chips 211 to 214 areseparated from each other in a longitudinal direction of the lightemitting device 200. However, it should be understood that arrangementof the light emitting chips may be modified in various ways in otherembodiments.

The wavelength conversion member 120 is disposed to cover an uppersurface of each of the first to fourth light emitting chips 211 to 214.Here, the wavelength conversion member 120 may have a width equal to awidth from one side of the first light emitting chip 211 disposed at oneside of the substrate to one side of the fourth light emitting chip 214disposed at the other side thereof. That is, one side surface of thewavelength conversion member 120 may be collinear with one side surfaceof the first light emitting chip 211 and the other side surface of thewavelength conversion member 120 may be collinear with one side surfaceof the fourth light emitting chip 214. Here, the one side surface of thefirst light emitting chip 211 refers to a side surface thereof oppositeto a side surface of the first light emitting chip 211 facing the secondlight emitting chip 212. In addition, the other side surface of thefourth light emitting chip 214 refers to a side surface thereof oppositeto a side surface of the fourth light emitting chip 214 facing the thirdlight emitting chip 213. That is, the one side surface of the firstlight emitting chip 211 and the one side surface of the fourth lightemitting chip 214 face an inner wall of the barrier member 140, as shownin FIG. 6.

Here, the wavelength conversion member 120 may have a thickness set inconsideration of viewing angle of the first to fourth light emittingchips 211 to 214 disposed adjacent to one another. For example, thewavelength conversion member 120 may have a thickness to allow at leastsome fractions of light emitted from adjacent light emitting chips tocross each other inside the wavelength conversion member 120. Further,the wavelength conversion member 120 may have a thickness to allow atleast some fractions of light emitted from adjacent light emitting chipsto cross each other at a central portion of the wavelength conversionmember 120.

The reflective member 130 is formed to surround the side surfaces of thewavelength conversion member 120 formed to cover the upper surfaces ofthe first to fourth light emitting chips 211 to 214.

As such, the light emitting device 200 according to the secondembodiment includes the plurality of light emitting chips and thus hasan elongated luminous surface. In addition, the light emitting device200 according to the second embodiment includes the reflective member130 surrounding the wavelength conversion member 120, thereby preventinglight blurring around the wavelength conversion member 120.

FIG. 7 and FIG. 8 are views of a light emitting device according to athird embodiment of the present disclosure. FIG. 7 is a top view of thelight emitting device 300 according to the third embodiment. FIG. 8 is across-sectional view of the light emitting device 300 according to thethird embodiment.

The light emitting device 300 according to the third embodiment includesa first light emitting chip 311, a second light emitting chip 312, afirst wavelength conversion member 321, a second wavelength conversionmember 322, a reflective member 130, a barrier member 330, and a circuitboard 150.

The first light emitting chip 311 is spaced apart from the second lightemitting chip 312 in a lateral direction. The barrier member 330 isdisposed between the first light emitting chip 311 and the second lightemitting chip 312.

The first wavelength conversion member 321 is disposed on an uppersurface of the first light emitting chip 311 and the second wavelengthconversion member 322 is disposed on the second light emitting chip 312.

The first wavelength conversion member 321 and the second wavelengthconversion member 322 may be formed of a mixture of a transparent resin,such as a silicone resin or an epoxy resin, glass or a ceramic materialand a wavelength conversion material that converts wavelengths of light.

In some embodiments, light having passed through the first wavelengthconversion member 321 may have a different color from light havingpassed through the second wavelength conversion member 322. The firstlight emitting chip 311 and the second light emitting chip 312 may emitlight having the same wavelength, and the first wavelength conversionmember 321 and the second wavelength conversion member 322 may containdifferent wavelength conversion materials that convert light intodifferent wavelengths. Alternatively, the first light emitting chip 311and the second light emitting chip 312 may emit light having differentwavelengths, and the first wavelength conversion member 321 and thesecond wavelength conversion member 322 may contain different wavelengthconversion materials. For example, light generated through combinationof the first light emitting chip 311 and the first wavelength conversionmember 321 may be white light and light generated through combination ofthe second light emitting chip 312 and the second wavelength conversionmember 322 may be yellow light. Here, white light may be used for alighting lamp for securing a vehicle driver's visual field and yellowlight may be used for a warning lamp for informing a vehicle driver ofdanger or emergency.

As in the first embodiment, the first wavelength conversion member 321and the second wavelength conversion member 322 may further include areflective material (not shown) to improve reflectivity of light.

The reflective member 130 is formed to surround side surfaces of each ofthe first wavelength conversion member 321 and the second wavelengthconversion member 322. Light having passed through the side surfaces ofthe first wavelength conversion member 321 is reflected by thereflective member 130. In addition, light having passed through the sidesurfaces of the second wavelength conversion member 322 is reflected bythe reflective member 130. Accordingly, the light emitting device canprevent light blurring at the periphery of each of the first wavelengthconversion member 321 and the second wavelength conversion member 322.

FIG. 9 is a graph depicting brightness of the light emitting deviceaccording to the third embodiment of the present disclosure. FIG. 9shows brightness of light depending upon distance from a center of thelight emitting device 300.

Referring to FIG. 9, Portion A2 shows that light is completely blockedbetween the first wavelength conversion member 321 and the barriermember 330. In addition, Portion B2 shows that light is not emittedthrough the barrier member 330 between the first wavelength conversionmember 321 and the second wavelength conversion member 322. Further,Portion C2 shows that light is completely blocked between the secondwavelength conversion member 322 and the barrier member 330. As such,the light emitting device 300 according to this embodiment can preventlight from passing through the barrier member 330 using the reflectivemember 130. Accordingly, the light emitting device 300 according to thisembodiment can prevent light blurring around the periphery of each ofthe first wavelength conversion member 321 and the second wavelengthconversion member 322. As a result, the light emitting device 300according to this embodiment can prevent interference of light havingtwo different colors while allowing simultaneous emission of lightthrough the first wavelength conversion member 321 and the secondwavelength conversion member 322.

According to this embodiment, the barrier member 330 may be divided intoan outer wall 332 and an inner wall 331, as shown in FIG. 8. The innerwall 331 refers to a portion of the barrier member 330 formed betweenthe first light emitting chip 311 and the second light emitting chip 312and between the first wavelength conversion member 321 and the secondwavelength conversion member 322.

The outer wall 332 refers to a portion of the barrier member 330 formedto surround an outer periphery constituted by the first light emittingchip 311 and the first wavelength conversion member 321, the secondlight emitting chip 312, the second wavelength conversion member 322,and the inner wall 331. That is, the outer wall 332 is formed tosurround side surfaces of components inside the light emitting device300.

The outer wall 332 of the barrier member 330 is formed to have an uppersurface having a height gradually decreasing from the inner wall to theouter wall. That is, an upper portion of the outer wall 332 of thebarrier member 330 has a thickness gradually increasing in a downwarddirection thereof. In addition, the inner wall 331 of the barrier member330 has a convex upper surface. For example, referring to FIG. 8, thethickness of the outer wall 332 of the barrier member 330 graduallyincreases in the sequence of portion t1 of the barrier member 140 formedat one side of an upper portion of the reflective member 130, portion t2of the barrier member 140 formed at one side between the upper portionof the reflective member 130 and a lower portion thereof, and portion t3of the barrier member 140 formed at one side of the lower portion of thereflective member 130. In addition, an inner portion of the inner wall331 of the barrier member 330 has a height t4 that is greater thanheight t5 of both sides thereof.

The structures of the outer wall 332 and the inner wall 331 are obtainedthrough deposition of a material for the barrier member 330 inconsideration of a narrow space between the first light emitting chip311 and the second light emitting chip 312.

Upon deposition of the material for the barrier member 330 into a space,in which the barrier member 330 will be formed, with reference to theouter wall 332 formed in a wider space than the inner wall 331, thematerial may cover the upper surfaces of the first wavelength conversionmember 321 and the second wavelength conversion member 322 in a narrowspace. As a result, the light emitting device 300 is decreased inluminous area. Accordingly, for the light emitting device 300 accordingto this embodiment, the material for the barrier member 330 is depositedinto a space, in which the barrier member 330 will be formed, withreference to a space in which the inner wall 331 will be formed.Accordingly, the material for the barrier member 330 is deposited to asufficient height in a space between the first light emitting chip 311and the second light emitting chip 312, and is deposited to a lowerheight in other spaces than the upper surface of each of the firstwavelength conversion member 321 and the second wavelength conversionmember 322. As the deposited material is cured, the upper surface of theouter wall 332 bulges along the side surfaces of the reflective member130 and the upper surface of the inner wall 331 has a convex shape. Thatis, although the upper portion of the outer wall 332 has a thinstructure, the light emitting device 300 according to this embodimentincludes the reflective member 130, thereby preventing light blurringdespite the thin structure of the upper portion of the outer wall 332.Accordingly, the light emitting device 300 according to this embodimentcan solve the problems of reduction in luminous area and light blurring.

The convex upper surface of the inner wall 331 protrudes above the uppersurfaces of the first light emitting chip 311 and the second lightemitting chip 312. That is, the inner wall 331 has a sufficient heightbetween the first light emitting chip 311 and the second light emittingchip 312. With this structure, the inner wall 331 can prevent lightemitted from the first and second light emitting chips 311,312 fromcrossing or interfering with each other.

The light emitting device 300 according to this embodiment may furtherinclude light extraction members 340, as shown in FIG. 8. The lightextraction member 340 may be formed to cover the side surfaces of eachof the first light emitting chip 311 and the second light emitting chip312. In addition, the light extraction members 340 may be formed suchthat an outer wall of the light extraction member facing the barriermember 330 has a radius of curvature. In the light emitting device 300according to this embodiment, both side surfaces of the first lightemitting chip 311 are collinear with both side surfaces of the firstwavelength conversion member 321 and both side surfaces of the secondlight emitting chip 312 are collinear with both side surfaces of thesecond wavelength conversion member 322. Accordingly, the lightextraction member 340 formed on both side surfaces of each of the firstlight emitting chip 311 and the second light emitting chip 312 is formedto cover the lower surface of the reflective member 130.

The light extraction member 340 formed on the side surfaces of the firstlight emitting chip 311 reflects light emitted through the side surfacesof the first light emitting chip 311 toward the first wavelengthconversion member 321. In addition, the light extraction member 340formed on the side surfaces of the second light emitting chip 312reflects light emitted through the side surfaces of the second lightemitting chip 312 toward the second wavelength conversion member 322.

According to this embodiment, the light extraction member 340 is formedto a thickness gradually decreasing from an upper portion of each of thefirst light emitting chip 311 and the second light emitting chip 312 toa lower portion thereof and has a curved outer wall. Accordingly, alower portion of the side surface of the inner wall 331 has a curvedsurface. In addition, the lower portion of the inner wall 331 has agreater thickness t7 than a portion of the inner wall 331 adjacent to anupper portion of the light extraction member 340 and having a thicknesst6, as shown in FIG. 8.

For example, the light extraction member 340 may be formed of a siliconeresin. Alternatively, the light extraction member 340 may be formed of amixture of a silicone resin and a reflective material.

FIG. 10 and FIG. 11 are views of a light emitting device according to afourth embodiment of the present disclosure. FIG. 10 is a top view ofthe light emitting device 400 according to the fourth embodiment FIG. 11is a cross-sectional view of the light emitting device 400 according tothe fourth embodiment.

The light emitting device 400 according to the fourth embodimentincludes a first light emitting chip 311, a second light emitting chip312, a first wavelength conversion member 321, a second wavelengthconversion member 322, reflective members 130, protective members 410, abarrier member 330, and a circuit board 150.

The first wavelength conversion member 321 is disposed on an uppersurface of the first light emitting chip 311 and the second wavelengthconversion member 322 is disposed on an upper surface of the secondlight emitting chip 312. In addition, each of the first wavelengthconversion member 321 and the second wavelength conversion member 322 isformed with the reflective member 130 surrounding the side surfacesthereof.

According to this embodiment, the light emitting device 400 furtherincludes the protective member 410 surrounding the side surfaces of eachof the reflective members 130, as shown in FIG. 10. The protectivemember 410 prevents the reflective member 130 from being corroded ordiscolored through reaction with hydrogen sulfide or oxygen generatedduring a process or due to an external environment.

When the reflective member 130 is corroded or discolored by externalmaterials, reflectivity of the reflective member 130 can be reduced.When light passes through a damaged portion of the reflective member130, the light emitting device 400 can suffer from light blurring. Inorder to prevent this problem, the light emitting device 400 accordingto this embodiment includes the protective members 410 adapted toprotect the reflective member 130. For example, the protective members410 may be composed of at least one layer selected from a siliconnitride (SiN_(X)) layer, a silicon oxide (SiO₂) layer, and a gold (Au)layer.

In addition, a bonding area of the barrier member 330 is increased bythe protective members 410, thereby improving bonding strength ofcomponents inside the light emitting device 400.

FIG. 12 and FIG. 13 are views of a light emitting device according to afifth embodiment of the present disclosure. FIG. 12 is a top view of thelight emitting device 500 according to the fifth embodiment. FIG. 13 isa cross-sectional view of the light emitting device 500 according to thefifth embodiment.

The light emitting device 500 includes a first light emitting chip 311,a second light emitting chip 312, a first wavelength conversion member321, a second wavelength conversion member 322, reflective members 130,protective members 410, a barrier member 510, and a circuit board 150.

According to this embodiment, the barrier member 510 is divided into anouter wall 511 and an inner wall 512. The inner wall 511 refers to aportion of the barrier member 510 formed between the first lightemitting chip 311 and the second light emitting chip 312 and between thefirst wavelength conversion member 321 and the second wavelengthconversion member 322. In addition, the outer wall 512 refers to aportion of the barrier member 510 formed to surround side surfaces ofthe first light emitting chip 311, the first wavelength conversionmember 321, the second light emitting chip 312 and the second wavelengthconversion member 322 excluding a portion of the barrier member 510 onwhich the inner wall 511 is disposed. Here, the reflective members 130and the protective members 410 may be formed between the firstwavelength conversion member 321 and the second wavelength conversionmember 322.

The barrier member 510 may be formed of a mixture of an epoxy orsilicone resin and fillers. For example, the fillers may include atleast one selected from titanium dioxide (TiO₂) for high refractivityand glass fibers for enhancement of strength. Strength of the barriermember 510 may be changed depending upon the amount of the fillerstherein. That is, increase in amount of the fillers in the resin resultsin increase in strength of the barrier member 510.

The barrier member 510 may be formed by dispensing or screen printingthe resin containing the fillers. Since dispensing enables precisedeposition of a material in a narrow space through a narrow outlet of adispenser, the barrier member 510 can be precisely formed. However,dispensing requires a material for the barrier member 510 to have lowviscosity allowing the material to pass through the narrow outlet of thedispenser. The resin containing a large amount of the fillers has highviscosity, thereby making it difficult for the resin to form the barriermember 510 having high strength.

In this embodiment, the inner wall 511 of the barrier member 510 isformed by dispensing a material having a small amount of the fillersinto a narrow space between the first light emitting chip 311 and thesecond light emitting chip 312. In addition, the outer wall 512 of thebarrier member 510 is formed by screen printing a material having alarge amount of the fillers on outer peripheral portions of the firstlight emitting chip 311 and the second light emitting chip 312. As aresult, the barrier member 510 can be formed to include the outer wall512 having high strength and the inner wall 511 precisely filled in anarrow space.

With the barrier member 510, the light emitting device 500 can have highstrength while preventing light blurring and failure in light emission.

Although the light extraction members are not shown in FIG. 10 to FIG.13, the light emitting devices according to the embodiments shown inFIG. 10 to FIG. 13 may further include the light extraction members suchas the light extraction member 340 as described above in connection withFIG. 8.

FIG. 14 is a view of a light emitting device according to a sixthembodiment of the present disclosure. Referring to FIG. 14, the lightemitting device 600 according to the sixth embodiment includes a lightemitting chip 110, a wavelength conversion member 120, reflectivemembers 130, light extraction members 610, a barrier member 140, and acircuit board 150.

The light extraction members 610 are formed at both sides of the lightemitting chip 110. In addition, each of the light extraction members 610has a thickness gradually decreasing from an upper portion thereof inthe downward direction and includes a curved outer wall facing thebarrier member 140. According to this embodiment, the light extractionmembers 610 of the light emitting device 600 have a different structurefrom the light extraction members 340 of FIG. 8. The outer wall of thelight extraction member 340 of FIG. 8 protrudes towards the barriermember 140, whereas the outer wall of the light extraction member 340 ofFIG. 14 has a concave shape. However, it should be understood that thestructure of the light extraction member 610 is not limited thereto andmay be changed depending upon a light reflection direction, a process offorming the light extraction member 610, user selection, and the like.

The light extraction members 610 reflect light emitted through the sidesurfaces of the light emitting chip 110. Here, the thickness of thelight extraction member 610 at each position thereof, or the radius ofcurvature of the outer wall thereof may be determined such that lightcan be reflected by the light extraction members 610 to enter thewavelength conversion member 120.

In the light emitting device 600 according to this embodiment, the lightextraction members 610 reflect light emitted through the side surfacesof the light emitting chip 110 toward the wavelength conversion member120, thereby improving light extraction efficiency. Further, in thelight emitting device 600, the light extraction member 610 prevents thelight from passing through the barrier member 140 disposed at the sidesurfaces of the light emitting chip 110, thereby preventing lightblurring at the side surfaces of the barrier member 140.

FIG. 15 is a view of a light emitting device according to a seventhembodiment of the present disclosure. Referring to FIG. 15, the lightemitting device 700 according to the seventh embodiment includes aplurality of light emitting chips, a wavelength conversion member 120,reflective members 130, light extraction members 610, a barrier member140, and a circuit board 150. For example, the plurality of lightemitting chips includes a first light emitting chip 211 and a secondlight emitting chip 212. It should be understood that this structure isillustrated for convenience of description and the light emitting device700 may include more light emitting chips.

The light extraction members 710 as shown in FIG. 15 are formed at bothsides of each of the first light emitting chip 211 and the second lightemitting chip 212. In addition, the light extraction members 710 have athickness gradually decreasing from an upper portion thereof in thedownward direction and include a curved outer wall facing the barriermember 140.

In the above embodiment, the light extraction members are formed at bothsides of the light emitting chip while covering the entirety of thelower surface of the reflective member 130. However, in the lightemitting device 700 according to this embodiment, each of the lightextraction members 710 is formed at different locations from that of theabove embodiment.

Referring to FIG. 15, both side surfaces of the wavelength conversionmember 120 protrude outwards over the side surfaces of the first lightemitting chip 211 and the second light emitting chip 212. Each of thelight extraction members 610 is formed so as not to cover the lowersurface of the reflective member 130 while covering a lower surface of aportion of each of the wavelength conversion members 610 protrudingoutward over the side surfaces of the first light emitting chip 211 andthe second light emitting chip 212. In this structure, some fractions oflight refracted by the light extraction member 710 may travel to thewavelength conversion member 120 through the first light emitting chip211, or the second light emitting chip 212 and other fractions of thelight may travel directly to the wavelength conversion member 120through the light extraction member 710.

As such, the locations, thickness and radius of curvature of the lightextraction members 610 and 710 as shown in FIGS. 14-15 may be changed invarious ways by selection of those skilled in the art.

The first light emitting chip 211 and the second light emitting chip 212may be disposed such that at least some fractions of light emittedtherefrom cross each other inside the wavelength conversion member 120.

Further, the light extraction members 710 reflect light emitted throughthe side surfaces of the first light emitting chip 211 and the secondlight emitting chip 212 toward the wavelength conversion members 120.Here, some fractions of light emitted through the side surfaces of thefirst light emitting chip 211 and the second light emitting chip 212 andreflected by the light extraction members 710 may cross each otherinside the wavelength conversion members 120 depending upon the radiusof curvature of the light extraction members 710.

As such, the thickness of the wavelength conversion member 120 may begreater than a separation distance between the first light emitting chip211 and the second light emitting chip 212 so as to allow light emittedthrough the side surfaces of the first light emitting chip 211 and thesecond light emitting chip 212 to cross each other inside the wavelengthconversion member 120. For example, the separation distance t1 betweenthe first light emitting chip 211 and the second light emitting chip 212may be 190 μm or less. In addition, the wavelength conversion member 120may have a thickness t2 of 200 μm or less.

When at least some fractions of light emitted through the side surfacesof the first light emitting chip 211 and the second light emitting chip212 cross each other inside the wavelength conversion member 120 as inthis embodiment, light having passed through the upper surface of thewavelength conversion member 120 has improved uniformity, as comparedwith the case where the light emitted through the side surfaces thereofdoes not cross each other inside the wavelength conversion member 120.That is, the light emitting device 700 according to this embodiment hashigh light uniformity.

The above descriptions focus on the constitution and effects of thelight emitting device according to various embodiments when applied to avehicle lamp. However, it should be understood that the effects of thelight emitting device according to embodiments of the present disclosureare not limited to the vehicle lamp. The light emitting device accordingto the present disclosure may be applied not only to the vehicle lampbut also to display devices.

When light blurring occurs at a side surface of a light emitting devicein a backlight unit of a display device, the display device can sufferfrom a phenomenon in which an outer periphery of the display devicelooks brighter than the central thereof. In addition, the display devicecan suffer from a phenomenon in which the whole display screen issmeared. Further, the display device can suffer from reduction in thecontrast ratio and the viewing angle. Moreover, the display device cansuffer from color deviation, causing deterioration in color quality.

However, the light emitting device according to embodiments of thepresent disclosure can prevent light blurring at the side surface of thelight emitting device using the reflective member. Accordingly, when thelight emitting device according to the present disclosure is applied toa display device, the display device can prevent the phenomenon in whichthe outer periphery of the display device looks brighter than thecentral thereof, the smearing phenomenon, reduction in contrast ratioand viewing angle, and color deviation.

FIG. 16 and FIG. 17 are views of a light emitting device according to aneighth embodiment of the present disclosure. FIG. 16 is a top view ofthe light emitting device 800 according to the eighth embodiment andFIG. 17 is a cross-sectional view (I1-I2) of the light emitting device800 shown in FIG. 16.

The light emitting device 800 according to the eighth embodiment of thepresent disclosure includes a substrate, a plurality of light emittingchips 110, wavelength conversion members 120, reflective members 130,and a barrier member 330. The substrate may be a circuit board 150having a circuit pattern thereon.

The circuit board 150 includes an insulation layer 153 and anelectrically conductive circuit pattern formed on the insulation layer153. The circuit pattern includes a first circuit pattern 151, a secondcircuit pattern 152, and via holes 154. The first circuit pattern 151 isformed on an upper surface of the insulation layer 153. The secondcircuit pattern 152 is formed on a lower surface of the insulation layer153. The via holes 154 are formed through the insulation layer 153 toelectrically connect the first circuit pattern 151 to the second circuitpattern 152. The circuit pattern is electrically connected to theplurality of light emitting chips 110 mounted on the circuit board 150.Although the circuit board 150 is illustrated as the substrate havingthe light emitting chips 110 mounted thereon, it should be understoodthat the present disclosure is not limited thereto. The substrate may beselected from any type of substrate so long as the substrate iselectrically connected to the light emitting chip 110 mounted thereon tosupply electric power to the light emitting chips 110 for emission oflight.

Each of the light emitting chips 110 is electrically connected to thecircuit pattern of the circuit board 150. For example, the plurality oflight emitting chips 110 may be mounted on the circuit board 150 byflip-chip bonding.

The plurality of light emitting chips 110 electrically connected to thecircuit pattern may be individually operated in response to externalsignals. That is, each of the light emitting chips 110 may beindividually operated to emit light or stop emission of light.

However, it should be understood that this embodiment is not limitedthereto. The light emitting device 800 according to this embodiment mayinclude an array of a plurality of light emitting chips. Here, in thearray of light emitting chips, the light emitting chips are connected inseries or in parallel through the circuit pattern to operate at the sametime.

Referring to FIG. 17, the wavelength conversion member 120 is disposedon each of the light emitting chips 110. In addition, the reflectivemember 130 covers side surfaces of each of the wavelength conversionmembers 120, as shown in FIG. 16.

The barrier member 330 is formed on the circuit board 150 to cover sidesurfaces of the light emitting chips 110 and the reflective members 130.That is, the barrier member 330 is configured to expose an upper surfaceof each of the wavelength conversion members 120 and the reflectivemembers 130.

Further, the barrier member 330 may be formed of a silicone resin.Alternatively, the barrier member 330 may be formed of a silicone resincontaining fillers, such as a reflective material, glass fibers, and thelike. Here, an inner wall of the barrier member 330 may have a smalleramount of the fillers than an outer wall thereof, as in the fifthembodiment shown in FIG. 12 and FIG. 13. In the barrier member 330, theouter wall refers to a portion of the barrier member 330 between thelight emitting chips 110 and a side surface of the substrate 115 and theinner wall refers to a portion of the barrier member 330 disposedbetween the light emitting chips 110.

In recent years, there is tendency of miniaturization of the lightemitting chip 110 while requiring high image quality of display devices.In order to realize high quality, the degree of definition of thedisplay device can be increased by increasing the number of pixelsthereof. To this end, the display device is increased in the number oflight emitting chips 10 in the same region, thereby causing decrease inseparation distance between the light emitting chips 110. Furthermore,as the contrast between the pixels becomes clearer, the display devicecan realize higher image quality through improvement in the degree ofdefinition. However, when the light emitting chip 110 causing lightblurring is used in the display device, the display device can sufferfrom light interference between the pixels, thereby causingdeterioration in contrast between the pixels. As a result, the degree ofdefinition of the display device is deteriorated due to light blurringof the light emitting chip 110, thereby causing deterioration in imagequality of the display device.

The light emitting device 800 according to this embodiment includes thereflective member 130 covering the side surfaces of each of thewavelength conversion member 120 having a light exit surface throughwhich light is emitted, thereby preventing the light from being emittedfrom other portions of the wavelength conversion member 120 excludingthe light exit surface. Thus, the light emitting device 800 allows lightto be emitted from each of the light emitting chips 110 only in anupward direction thereof by the reflective members 130, therebypreventing the light from affecting regions in which other adjacentlight emitting chips 110 are disposed. Accordingly, the light emittingdevice 800 can prevent light interference between the pixels, therebyimproving definition of the display device.

FIG. 18 is a view of a light emitting device according to a ninthembodiment of the present disclosure. The light emitting device 900according to the ninth embodiment includes a circuit board 150, a lightemitting chip 110, a wavelength conversion member 120, a reflectivemember 930, and a barrier member 330.

According to this embodiment, the reflective member 930 covers the sidesurfaces of the wavelength conversion member 120 and the light emittingchip 110. The reflective member 930 including a metal is formed to coverthe side surfaces of the light emitting chip 110 without contacting apair of electrode pads 115.

One of the electrode pads 115 of the light emitting chip 110 iselectrically connected to an n-type semiconductor layer and the otherelectrode pad is electrically connected to a p-type semiconductor layer.In addition, the electrode pads 115 are exposed from the light emittingchip 110 and electrically connected to the circuit pattern of thecircuit board 150.

In the light emitting device 900 according to this embodiment, thereflective member 930 is formed to cover all side surfaces of the lightemitting chip 110 without contacting the electrode pads 115.

With this structure, the reflective member 930 prevents light fromemitted through the side surfaces of the barrier member 330 byreflecting light emitted through the side surfaces of the wavelengthconversion member 120 and the side surfaces of the light emitting chip110. Accordingly, even with a structure wherein the barrier member 330formed on the side surfaces of the wavelength conversion member 120 andthe light emitting chip 110 has a thin thickness, the light emittingdevice 900 can prevent light blurring. That is, the light emittingdevice 900 according to this embodiment allows reduction in thickness ofthe barrier member 330 formed on the side surfaces of the wavelengthconversion member 120 and the light emitting chip 110.

FIG. 19 to FIG. 21 are views of light emitting devices according totenth and eleventh embodiments of the present disclosure. FIG. 19 is atop view of the light emitting device according to the tenth embodiment.FIG. 20 is a cross-sectional view of the light emitting device accordingto the tenth embodiment. In addition, FIG. 21 is a cross-sectional viewof the light emitting device according to the eleventh embodiment.

Each of the light emitting devices 1000, 1100 according to the tenth andeleventh embodiments includes a circuit board 150, a plurality of lightemitting chips 110, a wavelength conversion member 120, a reflectivemember 930, and barrier members 330, 1110.

In the light emitting devices 1000, 1100 according to these embodiments,the plural light emitting chips 110 are mounted on the circuit board 150having an electrically conductive circuit pattern thereon. In addition,each of the light emitting chips 110 is electrically connected to thecircuit pattern of the circuit board 150.

The plurality of light emitting chips 110 electrically connected to thecircuit pattern may be individually operated in response to externalsignals. Alternatively, the plurality of light emitting chips 110 mayform an array of light emitting chips operating at the same time, andthe light emitting devices 1000, 1100 as shown in FIGS. 19-21 mayinclude a plurality of arrays mounted on the circuit board 150.

According to this embodiment, each of the light emitting chips 110 isformed on an upper surface thereof with the wavelength conversionmembers 120. In addition, the reflective members 930 is formed tosurround the side surfaces of the light emitting chip 110 and the sidesurfaces of the wavelength conversion member 120. The wavelengthconversion member 120 and the reflective member 930 formed on each ofthe light emitting chips 110 will be described with reference to FIG.18.

Referring to FIG. 20, in the light emitting device 1000 according to thetenth embodiment, the barrier member 330 disposed at outer sides of thelight emitting chips 110 at opposite sides of the circuit board has athickness gradually increasing from an upper portion thereof in adownward direction thereof. That is, a portion of the barrier member 330disposed between each of the light emitting chips 110 and a side surfaceof the circuit board 150 has a thickness gradually increasing from anupper portion thereof in the downward direction. In addition, thebarrier member 330 disposed between the light emitting chips 110 has aconvex upper surface.

In the light emitting device 1000 according to the tenth embodiment, thebarrier member 330 is formed by dispensing. Here, when an excess of amaterial for the barrier member 330 is dispensed, the barrier member 330can partially cover a light exit surface of the wavelength conversionmember 120, thereby causing reduction in luminous area. Accordingly, inconsideration of this structure, the material for the barrier member 330may be ejected onto the circuit board 150 upon formation of the barriermember 330. Accordingly, the barrier member 330 disposed at the outersides of the light emitting chips 110 at the opposite sides of thecircuit board has a lower height than the upper surface of thewavelength conversion member 120. Here, the material for the barriermember 330 is moved along the surface of the reflective member 930 dueto surface tension, thereby providing a structure where the portion ofthe barrier member 330 disposed at the outer sides of the light emittingchips 110 at the opposite sides of the circuit board has a thicknessgradually decreasing from a lower portion thereof in an upward directionthereof.

Further, a region between the light emitting chips 110 is narrower thana region between one side of the circuit board 150 and a side surface ofeach of the light emitting chips 110 at the opposite sides of thecircuit board 150. Accordingly, when a certain amount of the materialfor the barrier member 330 is ejected to each region, a predeterminedamount of the material can be deposited on the region between the lightemitting chips 110. Here, the barrier member 330 can have a convex uppersurface by curing the material for the barrier member 330, as shown inFIG. 20.

Referring to FIG. 21, in the light emitting device 1100 according to theeleventh embodiment, the barrier member 1110 may have a flat uppersurface. For example, the barrier member 1110 may be formed by screenprinting. The barrier member 1110 may be formed by depositing apredetermined amount of the material for the barrier member 1110 in eachregion through a mask having openings corresponding to locations atwhich the barrier member 1110 will be formed. Since screen printing isperformed by depositing a predetermined amount of the materialcorresponding to each region, the upper surface of the barrier member1110 can have a flat structure.

Alternatively, the barrier member 1110 may be formed by dispensing.Here, the material for the barrier member 1110 may be ejected in anexcess amount to each region. Then, the barrier member 1110 covering theupper surface of the wavelength conversion member 120 and the uppersurface of the reflective member 930 is removed by polishing in variousways, whereby the upper surface of the barrier member 1110 can beflattened.

It should be understood that the barrier member 1110 having a flat uppersurface is not limited to this embodiment of the present disclosure.That is, the barrier member 1110 having a flat upper surface may beapplied to light emitting devices according to other embodiments of thepresent disclosure.

FIG. 22 to FIG. 25 are views of light emitting devices according totwelfth to fifteenth embodiments of the present disclosure. Each of thelight emitting devices 1200, 1300, 1400, 1500 according to the twelfthto fifteenth embodiments includes a circuit board 150, a light emittingchip 110, a wavelength conversion member 120, a first reflective member1210, a second reflective member 1220, and a barrier member 1110.

Here, the first reflective member 1210 corresponds to the reflectivemember according to the other embodiments described above. Referring toFIG. 22 and FIG. 24, the light emitting devices 1200, 1400 have astructure wherein the first reflective member 1210 covers only the sidesurfaces of the wavelength conversion member 120. However, it should beunderstood that the light emitting devices 1200, 1400 are not limited tothis structure. Like the reflective member 130 shown in FIG. 18, thefirst reflective member 1210 may be formed to cover the side surfaces ofthe light emitting chip 110 and the wavelength conversion member 120.

In addition, referring to FIG. 22 and FIG. 24, in the light emittingdevice 1200, 1400, the barrier member 1110 has a flat upper surface.However, it should be understood that the barrier member 1110 of each ofthe light emitting devices 1200, 1400 is not limited thereto. Like thebarrier member 330 shown in FIG. 20, the barrier member 1110 may have astructure wherein the thickness of the barrier member 1110 graduallyincreases from an upper portion thereof in the downward directionthereof.

The second reflective member 1220 covers at least part of an uppersurface of the barrier member 1110.

Some fraction of light traveling toward the first reflective member 1210may be directed toward the upper surface of the barrier member 1110through the first reflective member 1210 and the barrier member 1110instead of being reflected by the first reflective member 1210.Furthermore, as shown in FIG. 22 and FIG. 24, in the structure whereinthe first reflective member 1210 is formed to cover only the sidesurfaces of the wavelength conversion member 120 corresponding thereto,light emitted through the side surfaces of the light emitting chip 110may travel toward the upper surface of the barrier member 1110 afterpassing through the barrier member 1110.

The second reflective member 1220 reflects light having passed throughthe barrier member 1110 or through both the first reflective member 1210and the barrier member 1110 and reaching the second reflective member1220. The second reflective member 1220 may be formed of the samematerial as the first reflective member 1210. Alternatively, the secondreflective member 1220 adapted to reflect light may be formed of adifferent material from the first reflective member 1210.

Referring to FIG. 22, in the light emitting device 1200 according to thetwelfth embodiment, the second reflective member 1220 covers the uppersurface of the first reflective member 1210 and a portion of the uppersurface of the barrier member 1110. Accordingly, the barrier member 1110of the light emitting device 1200 is not exposed between the firstreflective member 1210 and the second reflective member 1220.

Alternatively, the second reflective member 1220 may be formed tosurround the periphery of the upper surface of the first reflectivemember 1210 instead of covering the upper surface of the firstreflective member 1210. In this embodiment, the second reflective member1220 may contact the periphery of the upper surface of the firstreflective member 1210. Accordingly, the barrier member 1110 may not beexposed between the first reflective member 1210 and the secondreflective member 1220.

In the light emitting device 1200 according to the twelfth embodiment,the barrier member 1110 is not exposed between the first reflectivemember 1210 and the second reflective member 1220, thereby preventinglight emission between the first reflective member 1210 and the secondreflective member 1220.

FIG. 23 is a top view of the light emitting device 1300 according to thethirteenth embodiment, which includes a plurality of light emittingchips 110 mounted on the circuit board 150. In the light emitting device1300 according to the thirteenth embodiment, the wavelength conversionmember 120, the first reflective member 1210 and the second reflectivemember 1220 formed on each of the light emitting chips 110 are the sameas those of the light emitting device 1200 according to the twelfthembodiment.

Referring to FIG. 24, in the light emitting device 1400 according to thefourteenth embodiment, the second reflective member 1220 covers theentirety of the upper surface of the barrier member 1110. Here, thesecond reflective member 1220 may be formed to cover the upper surfaceof the first reflective member 1210, as shown in FIG. 24. Alternatively,the second reflective member 1220 may be formed to surround theperiphery of the upper surface of the first reflective member 1210instead of covering the upper surface of the first reflective member1210.

FIG. 25 is a top view of the light emitting device 1500 according to thefifteenth embodiment, which includes a plurality of light emitting chips110 mounted on the circuit board 150. In the light emitting device 1500according to the fifteenth embodiment, the wavelength conversion member120, the first reflective member 1210 and the second reflective member1220 formed on each of the light emitting chips 110 are the same asthose of the light emitting device 1400 according to the fourteenthembodiment.

The light emitting devices 1200, 1300, 1400, 1500 according to theseembodiments secure double prevention of emission of light through thebarrier member 1110 using the first reflective member 1210 and thesecond reflective member 1220. Accordingly, the light emitting devices1200, 1300, 1400, 1500 can more securely prevent light blurring.

In addition, the light emitting devices 1200, 1300, 1400, 1500 accordingto these embodiments can effectively prevent emission of light throughthe upper surface of the barrier member 1110 even with reduction inthickness of the first reflective member 1210 using the secondreflective member 1220. Alternatively, the light emitting devices 1200,1300, 1400, 1500 according to these embodiments can effectively preventemission of light through the upper surface of the barrier member 1110even with reduction in thickness of the second reflective member 1220using the first reflective member 1210. Accordingly, the light emittingdevices 1200, 1300, 1400, 1500 according to these embodiments enablereduction in width or thickness, as compared with the structureincluding a single reflective member.

Although some embodiments have been described herein with reference tothe accompanying drawings, it should be understood that theseembodiments are provided for illustration only and are not to beconstrued in any way as limiting the present disclosure. Therefore, itshould be understood that the scope of the present disclosure should bedefined by the appended claims and equivalents thereto.

1. A light emitting device, comprising: a substrate; a light emittingregion disposed on the substrate and including a first light emittingelement and a second light emitting element that are configured to emitdifferent wavelengths of light; and a barrier member comprising: aninner portion disposed between the first light emitting element and thesecond light emitting element and having a surface located further awayfrom the substrate than surfaces of the first light emitting element andthe second light emitting element; an outer portion disposed in an outerperiphery of the light emitting region and having a surface connected tothe surface of the inner portion.
 2. The light emitting device of claim1, wherein the first light emitting element and the second lightemitting element are configured to operate independently from eachother.
 3. The light emitting device of claim 1, wherein the barriermember includes fillers such that the outer portion of the barriermember includes a greater amount of the fillers than the inner portionof the barrier member.
 4. The light emitting device of claim 1, whereinthe surface of the inner portion and the surface of the outer portionare flat.
 5. The light emitting device of claim 1, wherein the lightemitting region includes additional light emitting elements such thatthe additional light emitting elements and the first light emittingelement and the second light emitting element are arranged in rows andcolumns.
 6. The light emitting device of claim 1, further comprising: areflective area including materials capable of reflecting light emittedfrom the first light emitting element and the second light emittingelement and disposed to be in contact with the inner portion of thebarrier member.
 7. The light emitting device of claim 1, furthercomprising: a light passage structure disposed over the first lightemitting element and the second light emitting element and having athickness greater than a separation distance between the first lightemitting element and the second light emitting element.
 8. A lightemitting device, comprising: a substrate; a light emitting regiondisposed on the substrate and including a first light emitting elementand a second light emitting element that are configured to emit lightcorresponding to different colors from each other; and a barrier membercomprising: an inner portion disposed between the first light emittingelement and the second light emitting element; an outer portionsurrounding the light emitting region, and wherein the first lightemitting element and the second light emitting element are separated bya separation distance that is 190 μm or less.
 9. The light emittingdevice of claim 8, wherein the barrier member includes materials havingdifferent reflectivity with respect to the light.
 10. The light emittingdevice of claim 8, wherein the barrier member includes fillers such thatthe outer portion of the barrier member includes a greater amount of thefillers than the inner portion of the barrier member.
 11. The lightemitting device of claim 8, wherein the surface of the inner portion andthe surface of the outer portion are flat.
 12. The light emitting deviceof claim 8, wherein the light emitting region includes additional lightemitting elements such that the additional light emitting elements andthe first light emitting element and the second light emitting elementare arranged in rows and columns.
 13. The light emitting device of claim8, further comprising: a reflective area including materials capable ofreflecting light emitted from the first light emitting element and thesecond light emitting element and disposed to be in contact with theinner portion of the barrier member.
 14. The light emitting device ofclaim 8, further comprising: a light passage structure disposed over thefirst light emitting element and the second light emitting element andconfigured to allow light emitted from the first light emitting elementand the second light emitting element to cross each other inside thelight passage structure.
 15. A light emitting device, comprising: asubstrate; a light emitting region disposed over the substrate andincluding a first light emitting element and second light emittingelement, each of the first light emitting element and the second lightemitting element including a first semiconductor layer having a firstconductivity type and a second semiconductor layer having a secondconductivity type; bonding material disposed on the substrate andelectrically connected to the first semiconductor layer and the secondsemiconductor layer of each of the first light emitting element and thesecond light emitting element, the bonding material configured toprovide electrical paths to electrically connect the substrate to thefirst light emitting element and the second by conductive material; anda barrier member comprising: an inner portion disposed between the firstlight emitting element and the second light emitting element and havinga surface located higher than surfaces of the first light emittingelement and the second light emitting element; an outer portionsurrounding an outer periphery of the light emitting region.
 16. Thelight emitting device of claim 15, wherein the surface of the innerportion is connected to an surface of the outer portion.
 17. The lightemitting device of claim 15, wherein the first light emitting elementand the second light emitting element are configured to operateindependently from each other.
 18. The light emitting device of claim15, wherein the barrier member includes fillers such that the outerportion of the barrier member includes a greater amount of the fillersthan the inner portion of the barrier member.
 19. The light emittingdevice of claim 15, wherein the surface of the inner portion and thesurface of the outer portion are flat.
 20. The light emitting device ofclaim 15, further comprising: a reflective area including materialscapable of reflecting light emitted from the first light emittingelement and the second light emitting element and disposed to be incontact with the inner portion of the barrier member.
 21. The lightemitting device of claim 15, further comprising: a light passagestructure disposed over the first light emitting element and the secondlight emitting element and having a thickness greater than a separationdistance between the first light emitting element and the second lightemitting element.